The present invention relates to an enzymatic composition capable of killing or inhibiting microbial cells or micro-organisms present, e.g., in laundry, on hard surfaces, in water systems, on skin, on teeth or on mucous membranes. The present invention also relates to the use of said enzymatic composition for preserving food products, cosmetics, paints, coatings, etc.
Various enzymatic antimicrobial compositions are known in the art. For instance, WO 94/04127 discloses stabilized dentifrice compositions which are capable of producing antimicrobially effective concentrations of hypothiocyanite ions. The compositions contain an oxidoreductase capable of producing hydrogen peroxide and a peroxidase enzyme capable of oxidizing thiocyanate ions normally present in saliva to antimicrobial hypothiocyanite ions. Suitable peroxidases include lactoperoxidase, myeloperoxidase, salivary peroxidase and chloroperoxidase.
In EP-A-0 500 387 enzymatic antimicrobial compositions are disclosed comprising a haloperoxidase, e.g., myelo-peroxidase, eosinophil oxidase, lactoperoxidase and chloroperoxidase, which selectively binds to and inhibits the growth of target micro-organisms in the presence of peroxide and halide.
WO 95/27046 discloses an antimicrobial composition comprising a Vanadium chloroperoxidase, halide ions, and hydrogen peroxide or a hydrogen peroxide-generating agent.
WO 96/38548 discloses an antimicrobial composition comprising a haloperoxidase, a halide ion, a peroxide generating agent and an amino acid.
WO 97/42825 discloses an antimicrobial composition comprising a peroxidase, a hydrogen peroxide source and an enhancing agent of the phenothiazine-type or of the acetosyringate-type.
The object of the present invention is to provide a composition for killing or inhibiting microbial cells.
According to the invention it has been found that an antimicrobial composition comprising a phenol oxidizing enzyme system and an enhancing agent comprising a xe2x80x94COxe2x80x94NOHxe2x80x94 group is very effective for killing or inhibiting microbial cells.
Thus, based on these findings, the present invention provides as a first aspect:
An enzymatic antimicrobial composition comprising a phenol oxidizing enzyme system and an enhancing agent of the following formula: 
in which A and B independently of each other are: 
or B is H or C1-16-alkyl, said alkyl may contain hydroxy, ether or ester groups, and R2, R3, R4, R5 and R6 independently of each other are H, OH, NH2, COOH, SO3H, C1-12-alkyl, acyl, NO2, CN, Cl, CF3, NOHxe2x80x94CO-phenyl, COxe2x80x94NOH-phenyl, C1-6-COxe2x80x94NOHxe2x80x94A, COxe2x80x94NOHxe2x80x94A, COR12, phenyl-COxe2x80x94NOHxe2x80x94A, OR7, NR8R9, COOR10, or NOHxe2x80x94COxe2x80x94R11, wherein R7, R8, R9, R10, R11 and R12 are C1-12-alkyl or acyl.
In further aspects, the present invention relates to methods for killing or inhibiting microbial cells, e.g. in laundry, in cosmetic products or on hard surfaces.
In still further aspects, the present invention relates to use of an enzymatic antimicrobial composition for cleaning of contact lenses, for cleaning of water systems, for preserving of paint, and in a cleaning-in-place system.